Commuter travel requirement leads to such congestion for many urban areas that local governments have now commenced using penalties to discourage commuters from using private cars. For example, the access charge in London, road tolls, petrol taxes etc. At the same time public bodies are using subsidies to encourage bus companies and the like to run uneconomic services.
Typically transport systems use public transport to move commuters from a series of pickup locations to one of a series of destination locations. If commuters wish to go to a location which is not on the route taken by their chosen vehicle they must change en route to another vehicle having a different series of destinations. Such a system produces delays both in waiting for a transport vehicle, in waiting in a transport vehicle while the vehicle takes on more commuters or lets some off at intermediate stops, and in transferring between routes. Additionally in many cases there is no public transport route to a place sufficiently close to a commuter's destination.
It is known to use car pooling in which persons who have made personal contact with others take them as passengers in their own car, usually for a negotiated fee, to the same destination as the driver: This system relies on the personal contact, or on complex interactive scheduling systems which take commuters time to utilise, and so is not effective in mass commuter situations. It has additional drawbacks in that the time of travel to and from work must be the same for all the commuters in a single car, a situation which becomes more and more difficult to meet as the number of commuters in a car increases.
It is also known to have “Park & Ride” schemes, where passengers park their cars and travel in large vehicles (e.g. busses & trains & trams). These systems have long delays awaiting vehicles, and high costs of commercially operated large vehicles including fixed costs and drivers.
We recognise that excessive vehicles for given roads create congestion. The first solution is to build bigger roads, with their long lead times and high capital costs, and the second is to develop and encourage use of public transport, car pooling and park and ride to increase traveller density on arterial roads for a given vehicle density. The problems with public transport are the result of tradeoffs of vehicle size and route frequency versus the cost of a driver and running a route with an underfilled bus or tram. In addition such a system suffers generic delays while the vehicle takes on or lets off passengers at en route stops. This can be obviated by using through flow methods in the vehicle, and by having large doors in comparison to the seating area, but there still remains the problem of transiting between multiple stops with acceleration and deceleration times for each.
One initial problem with normal car pooling systems is in the need for personal contact between the driver and passengers to both establish the initial contact and to verify that the prospective passengers are persons of good repute whom the driver has no major objections to transporting.
A second problem is the inflexibility of travel timing for members of the car pool who must all arrive at and leave work together.
A third problem is the natural resistance of participants to sharing their “private space” in a car, and the need for “cultural change” marketing to change this perspective.
Internet moderated car pools require communication and negotiation time setting up a ride for each day, and require the participants to make judgements about other riders or drivers “sight unseen”.
Park and ride has similar problems to public transport. Park and ride and public transport have the problem of distributed passenger trip destinations, whereby the transport vehicle does not usually take all passengers to their exact destination. On arrival at the ‘bus stop’ passengers must walk or take other modes to get to their final destination. Often the distance to the destination makes this total mode unattractive.
“Slugs and Bodysnatchers” programmes (where drivers pick up hitchhikers to get use of HOV lanes [e.g. bus lanes]) have developed spontaneously in some cities, but work only in the presence of parallel bus routes to provide for riders who cannot get a lift, and generally are higher risk, and more uncertain.